A study to examine changes in exposure to cigarette smoke chemicals when a smoker switches to using a tobacco heating product. Part I: study design
A tobacco heating product (THP), glo™, which heats rather than combusts tobacco and produces significantly reduced machine yields of chemical toxicants compared to combustible cigarettes, was assessed in this study. Biomarker of exposure (BoE) studies are an important tool in determining whether this reduction in toxicant emissions translates to actual reductions in human exposure to cigarette smoke toxicants when smokers switch to using glo™. Data from such studies may potentially be required as part of a regulatory package, particularly as one aspect of a modified-risk assessment of a novel product.
This presentation (Part I of II) will outline the design of a two-centre, in-clinic (confinement), forced-switching, randomised controlled clinical study, performed in Fukuoka, Japan (UMIN000024988, ISRCTN14301360) evaluating this novel THP. In this study, we compared baseline levels of selected BoE to cigarette smoke toxicants in the exhaled breath and urine of 180 smokers, to those seen when the smokers either remained smoking combustible cigarettes, switched to using a THP, or quit all tobacco use completely, for 5 days. We also assessed levels of two biomarkers of biological effect before and after switching, and determined nicotine pharmacokinetics for the study products. The study was approved by a local Institutional Review Board and was run in accordance with ICH-GCP. Subjects provided written informed consent prior to study participation and were deemed healthy following medical examination and clinical laboratory screening. Smoking status was verified by exhaled CO and urinary cotinine measurements.